1. Field of the Invention
The present invention relates to a thrustwasher and, more particularly, to a thrustwasher utilized in a differential gear assembly.
2. Related Art
Conventional differentials utilized in vehicle drivetrains typically include a face gear which is attached to the rotatable case and is driven by a pinion gear attached to a vehicle drive shaft. Known differentials further include pinion mate gears rotatably supported on stub shafts or pins secured within the rotatable case, with the pinion mate gears meshing with bevel side gears splined to the axle shafts.
Known differentials utilize a thrustwasher between the pinion mate gears and the differential case to minimize wear due to pinion mate rotation about the stub shafts mounted within the differential case. Historically, each thrustwasher has comprised a thin sheet metal stamping, heat-treated for wear resistance. In order to facilitate differential case assembly, the thrustwasher is usually designed with a spherical radius rather than a flat surface. Accordingly, a spherical radius is also required on the mating surfaces of the pinion mate gears and differential case. The spherical surfaces on the thrustwashers, pinion mate gears and differential case are relatively expensive to manufacture. Additionally, the use of thrustwashers having a spherical radius in a differential of the limited slip type, may compromise the required spatial envelope needed to accommodate the clutch pack of the limited slip differential for particular applications.
In view of the foregoing problems associated with known thrustwashers having a spherical radius, applicant's invention is herein presented.